Recipe package system.

recipe_engine/third_party/setuptools/command/easy_install.py

+#!/usr/bin/env python
+
+"""
+Easy Install
+------------
+
+A tool for doing automatic download/extract/build of distutils-based Python
+packages.  For detailed documentation, see the accompanying EasyInstall.txt
+file, or visit the `EasyInstall home page`__.
+
+__ https://pythonhosted.org/setuptools/easy_install.html
+
+"""
+
+from glob import glob
+from distutils.util import get_platform
+from distutils.util import convert_path, subst_vars
+from distutils.errors import DistutilsArgError, DistutilsOptionError, \
+    DistutilsError, DistutilsPlatformError
+from distutils.command.install import INSTALL_SCHEMES, SCHEME_KEYS
+from distutils import log, dir_util
+from distutils.command.build_scripts import first_line_re
+import sys
+import os
+import zipimport
+import shutil
+import tempfile
+import zipfile
+import re
+import stat
+import random
+import platform
+import textwrap
+import warnings
+import site
+import struct
+
+from setuptools import Command
+from setuptools.sandbox import run_setup
+from setuptools.py31compat import get_path, get_config_vars
+from setuptools.command import setopt
+from setuptools.archive_util import unpack_archive
+from setuptools.package_index import PackageIndex
+from setuptools.package_index import URL_SCHEME
+from setuptools.command import bdist_egg, egg_info
+from setuptools.compat import (iteritems, maxsize, basestring, unicode,
+                               reraise, PY2, PY3)
+from pkg_resources import (
+    yield_lines, normalize_path, resource_string, ensure_directory,
+    get_distribution, find_distributions, Environment, Requirement,
+    Distribution, PathMetadata, EggMetadata, WorkingSet, DistributionNotFound,
+    VersionConflict, DEVELOP_DIST,
+)
+import pkg_resources
+
+
+# Turn on PEP440Warnings
+warnings.filterwarnings("default", category=pkg_resources.PEP440Warning)
+
+
+sys_executable = os.environ.get('__PYVENV_LAUNCHER__',
+                                os.path.normpath(sys.executable))
+
+
+__all__ = [
+    'samefile', 'easy_install', 'PthDistributions', 'extract_wininst_cfg',
+    'main', 'get_exe_prefixes',
+]
+
+
+def is_64bit():
+    return struct.calcsize("P") == 8
+
+
+def samefile(p1, p2):
+    both_exist = os.path.exists(p1) and os.path.exists(p2)
+    use_samefile = hasattr(os.path, 'samefile') and both_exist
+    if use_samefile:
+        return os.path.samefile(p1, p2)
+    norm_p1 = os.path.normpath(os.path.normcase(p1))
+    norm_p2 = os.path.normpath(os.path.normcase(p2))
+    return norm_p1 == norm_p2
+
+
+if PY2:
+    def _to_ascii(s):
+        return s
+
+    def isascii(s):
+        try:
+            unicode(s, 'ascii')
+            return True
+        except UnicodeError:
+            return False
+else:
+    def _to_ascii(s):
+        return s.encode('ascii')
+
+    def isascii(s):
+        try:
+            s.encode('ascii')
+            return True
+        except UnicodeError:
+            return False
+
+
+class easy_install(Command):
+    """Manage a download/build/install process"""
+    description = "Find/get/install Python packages"
+    command_consumes_arguments = True
+
+    user_options = [
+        ('prefix=', None, "installation prefix"),
+        ("zip-ok", "z", "install package as a zipfile"),
+        ("multi-version", "m", "make apps have to require() a version"),
+        ("upgrade", "U", "force upgrade (searches PyPI for latest versions)"),
+        ("install-dir=", "d", "install package to DIR"),
+        ("script-dir=", "s", "install scripts to DIR"),
+        ("exclude-scripts", "x", "Don't install scripts"),
+        ("always-copy", "a", "Copy all needed packages to install dir"),
+        ("index-url=", "i", "base URL of Python Package Index"),
+        ("find-links=", "f", "additional URL(s) to search for packages"),
+        ("build-directory=", "b",
+         "download/extract/build in DIR; keep the results"),
+        ('optimize=', 'O',
+         "also compile with optimization: -O1 for \"python -O\", "
+         "-O2 for \"python -OO\", and -O0 to disable [default: -O0]"),
+        ('record=', None,
+         "filename in which to record list of installed files"),
+        ('always-unzip', 'Z', "don't install as a zipfile, no matter what"),
+        ('site-dirs=', 'S', "list of directories where .pth files work"),
+        ('editable', 'e', "Install specified packages in editable form"),
+        ('no-deps', 'N', "don't install dependencies"),
+        ('allow-hosts=', 'H', "pattern(s) that hostnames must match"),
+        ('local-snapshots-ok', 'l',
+         "allow building eggs from local checkouts"),
+        ('version', None, "print version information and exit"),
+        ('no-find-links', None,
+         "Don't load find-links defined in packages being installed")
+    ]
+    boolean_options = [
+        'zip-ok', 'multi-version', 'exclude-scripts', 'upgrade', 'always-copy',
+        'editable',
+        'no-deps', 'local-snapshots-ok', 'version'
+    ]
+
+    if site.ENABLE_USER_SITE:
+        help_msg = "install in user site-package '%s'" % site.USER_SITE
+        user_options.append(('user', None, help_msg))
+        boolean_options.append('user')
+
+    negative_opt = {'always-unzip': 'zip-ok'}
+    create_index = PackageIndex
+
+    def initialize_options(self):
+        if site.ENABLE_USER_SITE:
+            whereami = os.path.abspath(__file__)
+            self.user = whereami.startswith(site.USER_SITE)
+        else:
+            self.user = 0
+
+        self.zip_ok = self.local_snapshots_ok = None
+        self.install_dir = self.script_dir = self.exclude_scripts = None
+        self.index_url = None
+        self.find_links = None
+        self.build_directory = None
+        self.args = None
+        self.optimize = self.record = None
+        self.upgrade = self.always_copy = self.multi_version = None
+        self.editable = self.no_deps = self.allow_hosts = None
+        self.root = self.prefix = self.no_report = None
+        self.version = None
+        self.install_purelib = None  # for pure module distributions
+        self.install_platlib = None  # non-pure (dists w/ extensions)
+        self.install_headers = None  # for C/C++ headers
+        self.install_lib = None  # set to either purelib or platlib
+        self.install_scripts = None
+        self.install_data = None
+        self.install_base = None
+        self.install_platbase = None
+        if site.ENABLE_USER_SITE:
+            self.install_userbase = site.USER_BASE
+            self.install_usersite = site.USER_SITE
+        else:
+            self.install_userbase = None
+            self.install_usersite = None
+        self.no_find_links = None
+
+        # Options not specifiable via command line
+        self.package_index = None
+        self.pth_file = self.always_copy_from = None
+        self.site_dirs = None
+        self.installed_projects = {}
+        self.sitepy_installed = False
+        # Always read easy_install options, even if we are subclassed, or have
+        # an independent instance created.  This ensures that defaults will
+        # always come from the standard configuration file(s)' "easy_install"
+        # section, even if this is a "develop" or "install" command, or some
+        # other embedding.
+        self._dry_run = None
+        self.verbose = self.distribution.verbose
+        self.distribution._set_command_options(
+            self, self.distribution.get_option_dict('easy_install')
+        )
+
+    def delete_blockers(self, blockers):
+        for filename in blockers:
+            if os.path.exists(filename) or os.path.islink(filename):
+                log.info("Deleting %s", filename)
+                if not self.dry_run:
+                    if (os.path.isdir(filename) and
+                            not os.path.islink(filename)):
+                        rmtree(filename)
+                    else:
+                        os.unlink(filename)
+
+    def finalize_options(self):
+        if self.version:
+            print('setuptools %s' % get_distribution('setuptools').version)
+            sys.exit()
+
+        py_version = sys.version.split()[0]
+        prefix, exec_prefix = get_config_vars('prefix', 'exec_prefix')
+
+        self.config_vars = {
+            'dist_name': self.distribution.get_name(),
+            'dist_version': self.distribution.get_version(),
+            'dist_fullname': self.distribution.get_fullname(),
+            'py_version': py_version,
+            'py_version_short': py_version[0:3],
+            'py_version_nodot': py_version[0] + py_version[2],
+            'sys_prefix': prefix,
+            'prefix': prefix,
+            'sys_exec_prefix': exec_prefix,
+            'exec_prefix': exec_prefix,
+            # Only python 3.2+ has abiflags
+            'abiflags': getattr(sys, 'abiflags', ''),
+        }
+
+        if site.ENABLE_USER_SITE:
+            self.config_vars['userbase'] = self.install_userbase
+            self.config_vars['usersite'] = self.install_usersite
+
+        # fix the install_dir if "--user" was used
+        # XXX: duplicate of the code in the setup command
+        if self.user and site.ENABLE_USER_SITE:
+            self.create_home_path()
+            if self.install_userbase is None:
+                raise DistutilsPlatformError(
+                    "User base directory is not specified")
+            self.install_base = self.install_platbase = self.install_userbase
+            if os.name == 'posix':
+                self.select_scheme("unix_user")
+            else:
+                self.select_scheme(os.name + "_user")
+
+        self.expand_basedirs()
+        self.expand_dirs()
+
+        self._expand('install_dir', 'script_dir', 'build_directory',
+                     'site_dirs')
+        # If a non-default installation directory was specified, default the
+        # script directory to match it.
+        if self.script_dir is None:
+            self.script_dir = self.install_dir
+
+        if self.no_find_links is None:
+            self.no_find_links = False
+
+        # Let install_dir get set by install_lib command, which in turn
+        # gets its info from the install command, and takes into account
+        # --prefix and --home and all that other crud.
+        self.set_undefined_options(
+            'install_lib', ('install_dir', 'install_dir')
+        )
+        # Likewise, set default script_dir from 'install_scripts.install_dir'
+        self.set_undefined_options(
+            'install_scripts', ('install_dir', 'script_dir')
+        )
+
+        if self.user and self.install_purelib:
+            self.install_dir = self.install_purelib
+            self.script_dir = self.install_scripts
+        # default --record from the install command
+        self.set_undefined_options('install', ('record', 'record'))
+        # Should this be moved to the if statement below? It's not used
+        # elsewhere
+        normpath = map(normalize_path, sys.path)
+        self.all_site_dirs = get_site_dirs()
+        if self.site_dirs is not None:
+            site_dirs = [
+                os.path.expanduser(s.strip()) for s in
+                self.site_dirs.split(',')
+            ]
+            for d in site_dirs:
+                if not os.path.isdir(d):
+                    log.warn("%s (in --site-dirs) does not exist", d)
+                elif normalize_path(d) not in normpath:
+                    raise DistutilsOptionError(
+                        d + " (in --site-dirs) is not on sys.path"
+                    )
+                else:
+                    self.all_site_dirs.append(normalize_path(d))
+        if not self.editable:
+            self.check_site_dir()
+        self.index_url = self.index_url or "https://pypi.python.org/simple"
+        self.shadow_path = self.all_site_dirs[:]
+        for path_item in self.install_dir, normalize_path(self.script_dir):
+            if path_item not in self.shadow_path:
+                self.shadow_path.insert(0, path_item)
+
+        if self.allow_hosts is not None:
+            hosts = [s.strip() for s in self.allow_hosts.split(',')]
+        else:
+            hosts = ['*']
+        if self.package_index is None:
+            self.package_index = self.create_index(
+                self.index_url, search_path=self.shadow_path, hosts=hosts,
+            )
+        self.local_index = Environment(self.shadow_path + sys.path)
+
+        if self.find_links is not None:
+            if isinstance(self.find_links, basestring):
+                self.find_links = self.find_links.split()
+        else:
+            self.find_links = []
+        if self.local_snapshots_ok:
+            self.package_index.scan_egg_links(self.shadow_path + sys.path)
+        if not self.no_find_links:
+            self.package_index.add_find_links(self.find_links)
+        self.set_undefined_options('install_lib', ('optimize', 'optimize'))
+        if not isinstance(self.optimize, int):
+            try:
+                self.optimize = int(self.optimize)
+                if not (0 <= self.optimize <= 2):
+                    raise ValueError
+            except ValueError:
+                raise DistutilsOptionError("--optimize must be 0, 1, or 2")
+
+        if self.editable and not self.build_directory:
+            raise DistutilsArgError(
+                "Must specify a build directory (-b) when using --editable"
+            )
+        if not self.args:
+            raise DistutilsArgError(
+                "No urls, filenames, or requirements specified (see --help)")
+
+        self.outputs = []
+
+    def _expand_attrs(self, attrs):
+        for attr in attrs:
+            val = getattr(self, attr)
+            if val is not None:
+                if os.name == 'posix' or os.name == 'nt':
+                    val = os.path.expanduser(val)
+                val = subst_vars(val, self.config_vars)
+                setattr(self, attr, val)
+
+    def expand_basedirs(self):
+        """Calls `os.path.expanduser` on install_base, install_platbase and
+        root."""
+        self._expand_attrs(['install_base', 'install_platbase', 'root'])
+
+    def expand_dirs(self):
+        """Calls `os.path.expanduser` on install dirs."""
+        self._expand_attrs(['install_purelib', 'install_platlib',
+                            'install_lib', 'install_headers',
+                            'install_scripts', 'install_data', ])
+
+    def run(self):
+        if self.verbose != self.distribution.verbose:
+            log.set_verbosity(self.verbose)
+        try:
+            for spec in self.args:
+                self.easy_install(spec, not self.no_deps)
+            if self.record:
+                outputs = self.outputs
+                if self.root:  # strip any package prefix
+                    root_len = len(self.root)
+                    for counter in range(len(outputs)):
+                        outputs[counter] = outputs[counter][root_len:]
+                from distutils import file_util
+
+                self.execute(
+                    file_util.write_file, (self.record, outputs),
+                    "writing list of installed files to '%s'" %
+                    self.record
+                )
+            self.warn_deprecated_options()
+        finally:
+            log.set_verbosity(self.distribution.verbose)
+
+    def pseudo_tempname(self):
+        """Return a pseudo-tempname base in the install directory.
+        This code is intentionally naive; if a malicious party can write to
+        the target directory you're already in deep doodoo.
+        """
+        try:
+            pid = os.getpid()
+        except:
+            pid = random.randint(0, maxsize)
+        return os.path.join(self.install_dir, "test-easy-install-%s" % pid)
+
+    def warn_deprecated_options(self):
+        pass
+
+    def check_site_dir(self):
+        """Verify that self.install_dir is .pth-capable dir, if needed"""
+
+        instdir = normalize_path(self.install_dir)
+        pth_file = os.path.join(instdir, 'easy-install.pth')
+
+        # Is it a configured, PYTHONPATH, implicit, or explicit site dir?
+        is_site_dir = instdir in self.all_site_dirs
+
+        if not is_site_dir and not self.multi_version:
+            # No?  Then directly test whether it does .pth file processing
+            is_site_dir = self.check_pth_processing()
+        else:
+            # make sure we can write to target dir
+            testfile = self.pseudo_tempname() + '.write-test'
+            test_exists = os.path.exists(testfile)
+            try:
+                if test_exists:
+                    os.unlink(testfile)
+                open(testfile, 'w').close()
+                os.unlink(testfile)
+            except (OSError, IOError):
+                self.cant_write_to_target()
+
+        if not is_site_dir and not self.multi_version:
+            # Can't install non-multi to non-site dir
+            raise DistutilsError(self.no_default_version_msg())
+
+        if is_site_dir:
+            if self.pth_file is None:
+                self.pth_file = PthDistributions(pth_file, self.all_site_dirs)
+        else:
+            self.pth_file = None
+
+        PYTHONPATH = os.environ.get('PYTHONPATH', '').split(os.pathsep)
+        if instdir not in map(normalize_path, [_f for _f in PYTHONPATH if _f]):
+            # only PYTHONPATH dirs need a site.py, so pretend it's there
+            self.sitepy_installed = True
+        elif self.multi_version and not os.path.exists(pth_file):
+            self.sitepy_installed = True  # don't need site.py in this case
+            self.pth_file = None  # and don't create a .pth file
+        self.install_dir = instdir
+
+    def cant_write_to_target(self):
+        template = """can't create or remove files in install directory
+
+The following error occurred while trying to add or remove files in the
+installation directory:
+
+    %s
+
+The installation directory you specified (via --install-dir, --prefix, or
+the distutils default setting) was:
+
+    %s
+"""
+        msg = template % (sys.exc_info()[1], self.install_dir,)
+
+        if not os.path.exists(self.install_dir):
+            msg += """
+This directory does not currently exist.  Please create it and try again, or
+choose a different installation directory (using the -d or --install-dir
+option).
+"""
+        else:
+            msg += """
+Perhaps your account does not have write access to this directory?  If the
+installation directory is a system-owned directory, you may need to sign in
+as the administrator or "root" account.  If you do not have administrative
+access to this machine, you may wish to choose a different installation
+directory, preferably one that is listed in your PYTHONPATH environment
+variable.
+
+For information on other options, you may wish to consult the
+documentation at:
+
+  https://pythonhosted.org/setuptools/easy_install.html
+
+Please make the appropriate changes for your system and try again.
+"""
+        raise DistutilsError(msg)
+
+    def check_pth_processing(self):
+        """Empirically verify whether .pth files are supported in inst. dir"""
+        instdir = self.install_dir
+        log.info("Checking .pth file support in %s", instdir)
+        pth_file = self.pseudo_tempname() + ".pth"
+        ok_file = pth_file + '.ok'
+        ok_exists = os.path.exists(ok_file)
+        try:
+            if ok_exists:
+                os.unlink(ok_file)
+            dirname = os.path.dirname(ok_file)
+            if not os.path.exists(dirname):
+                os.makedirs(dirname)
+            f = open(pth_file, 'w')
+        except (OSError, IOError):
+            self.cant_write_to_target()
+        else:
+            try:
+                f.write("import os; f = open(%r, 'w'); f.write('OK'); "
+                        "f.close()\n" % (ok_file,))
+                f.close()
+                f = None
+                executable = sys.executable
+                if os.name == 'nt':
+                    dirname, basename = os.path.split(executable)
+                    alt = os.path.join(dirname, 'pythonw.exe')
+                    if (basename.lower() == 'python.exe' and
+                            os.path.exists(alt)):
+                        # use pythonw.exe to avoid opening a console window
+                        executable = alt
+
+                from distutils.spawn import spawn
+
+                spawn([executable, '-E', '-c', 'pass'], 0)
+
+                if os.path.exists(ok_file):
+                    log.info(
+                        "TEST PASSED: %s appears to support .pth files",
+                        instdir
+                    )
+                    return True
+            finally:
+                if f:
+                    f.close()
+                if os.path.exists(ok_file):
+                    os.unlink(ok_file)
+                if os.path.exists(pth_file):
+                    os.unlink(pth_file)
+        if not self.multi_version:
+            log.warn("TEST FAILED: %s does NOT support .pth files", instdir)
+        return False
+
+    def install_egg_scripts(self, dist):
+        """Write all the scripts for `dist`, unless scripts are excluded"""
+        if not self.exclude_scripts and dist.metadata_isdir('scripts'):
+            for script_name in dist.metadata_listdir('scripts'):
+                if dist.metadata_isdir('scripts/' + script_name):
+                    # The "script" is a directory, likely a Python 3
+                    # __pycache__ directory, so skip it.
+                    continue
+                self.install_script(
+                    dist, script_name,
+                    dist.get_metadata('scripts/' + script_name)
+                )
+        self.install_wrapper_scripts(dist)
+
+    def add_output(self, path):
+        if os.path.isdir(path):
+            for base, dirs, files in os.walk(path):
+                for filename in files:
+                    self.outputs.append(os.path.join(base, filename))
+        else:
+            self.outputs.append(path)
+
+    def not_editable(self, spec):
+        if self.editable:
+            raise DistutilsArgError(
+                "Invalid argument %r: you can't use filenames or URLs "
+                "with --editable (except via the --find-links option)."
+                % (spec,)
+            )
+
+    def check_editable(self, spec):
+        if not self.editable:
+            return
+
+        if os.path.exists(os.path.join(self.build_directory, spec.key)):
+            raise DistutilsArgError(
+                "%r already exists in %s; can't do a checkout there" %
+                (spec.key, self.build_directory)
+            )
+
+    def easy_install(self, spec, deps=False):
+        tmpdir = tempfile.mkdtemp(prefix="easy_install-")
+        download = None
+        if not self.editable:
+            self.install_site_py()
+
+        try:
+            if not isinstance(spec, Requirement):
+                if URL_SCHEME(spec):
+                    # It's a url, download it to tmpdir and process
+                    self.not_editable(spec)
+                    download = self.package_index.download(spec, tmpdir)
+                    return self.install_item(None, download, tmpdir, deps,
+                                             True)
+
+                elif os.path.exists(spec):
+                    # Existing file or directory, just process it directly
+                    self.not_editable(spec)
+                    return self.install_item(None, spec, tmpdir, deps, True)
+                else:
+                    spec = parse_requirement_arg(spec)
+
+            self.check_editable(spec)
+            dist = self.package_index.fetch_distribution(
+                spec, tmpdir, self.upgrade, self.editable,
+                not self.always_copy, self.local_index
+            )
+            if dist is None:
+                msg = "Could not find suitable distribution for %r" % spec
+                if self.always_copy:
+                    msg += " (--always-copy skips system and development eggs)"
+                raise DistutilsError(msg)
+            elif dist.precedence == DEVELOP_DIST:
+                # .egg-info dists don't need installing, just process deps
+                self.process_distribution(spec, dist, deps, "Using")
+                return dist
+            else:
+                return self.install_item(spec, dist.location, tmpdir, deps)
+
+        finally:
+            if os.path.exists(tmpdir):
+                rmtree(tmpdir)
+
+    def install_item(self, spec, download, tmpdir, deps, install_needed=False):
+
+        # Installation is also needed if file in tmpdir or is not an egg
+        install_needed = install_needed or self.always_copy
+        install_needed = install_needed or os.path.dirname(download) == tmpdir
+        install_needed = install_needed or not download.endswith('.egg')
+        install_needed = install_needed or (
+            self.always_copy_from is not None and
+            os.path.dirname(normalize_path(download)) ==
+            normalize_path(self.always_copy_from)
+        )
+
+        if spec and not install_needed:
+            # at this point, we know it's a local .egg, we just don't know if
+            # it's already installed.
+            for dist in self.local_index[spec.project_name]:
+                if dist.location == download:
+                    break
+            else:
+                install_needed = True  # it's not in the local index
+
+        log.info("Processing %s", os.path.basename(download))
+
+        if install_needed:
+            dists = self.install_eggs(spec, download, tmpdir)
+            for dist in dists:
+                self.process_distribution(spec, dist, deps)
+        else:
+            dists = [self.egg_distribution(download)]
+            self.process_distribution(spec, dists[0], deps, "Using")
+
+        if spec is not None:
+            for dist in dists:
+                if dist in spec:
+                    return dist
+
+    def select_scheme(self, name):
+        """Sets the install directories by applying the install schemes."""
+        # it's the caller's problem if they supply a bad name!
+        scheme = INSTALL_SCHEMES[name]
+        for key in SCHEME_KEYS:
+            attrname = 'install_' + key
+            if getattr(self, attrname) is None:
+                setattr(self, attrname, scheme[key])
+
+    def process_distribution(self, requirement, dist, deps=True, *info):
+        self.update_pth(dist)
+        self.package_index.add(dist)
+        if dist in self.local_index[dist.key]:
+            self.local_index.remove(dist)
+        self.local_index.add(dist)
+        self.install_egg_scripts(dist)
+        self.installed_projects[dist.key] = dist
+        log.info(self.installation_report(requirement, dist, *info))
+        if (dist.has_metadata('dependency_links.txt') and
+                not self.no_find_links):
+            self.package_index.add_find_links(
+                dist.get_metadata_lines('dependency_links.txt')
+            )
+        if not deps and not self.always_copy:
+            return
+        elif requirement is not None and dist.key != requirement.key:
+            log.warn("Skipping dependencies for %s", dist)
+            return  # XXX this is not the distribution we were looking for
+        elif requirement is None or dist not in requirement:
+            # if we wound up with a different version, resolve what we've got
+            distreq = dist.as_requirement()
+            requirement = requirement or distreq
+            requirement = Requirement(
+                distreq.project_name, distreq.specs, requirement.extras
+            )
+        log.info("Processing dependencies for %s", requirement)
+        try:
+            distros = WorkingSet([]).resolve(
+                [requirement], self.local_index, self.easy_install
+            )
+        except DistributionNotFound:
+            e = sys.exc_info()[1]
+            raise DistutilsError(
+                "Could not find required distribution %s" % e.args
+            )
+        except VersionConflict:
+            e = sys.exc_info()[1]
+            raise DistutilsError(
+                "Installed distribution %s conflicts with requirement %s"
+                % e.args
+            )
+        if self.always_copy or self.always_copy_from:
+            # Force all the relevant distros to be copied or activated
+            for dist in distros:
+                if dist.key not in self.installed_projects:
+                    self.easy_install(dist.as_requirement())
+        log.info("Finished processing dependencies for %s", requirement)
+
+    def should_unzip(self, dist):
+        if self.zip_ok is not None:
+            return not self.zip_ok
+        if dist.has_metadata('not-zip-safe'):
+            return True
+        if not dist.has_metadata('zip-safe'):
+            return True
+        return False
+
+    def maybe_move(self, spec, dist_filename, setup_base):
+        dst = os.path.join(self.build_directory, spec.key)
+        if os.path.exists(dst):
+            msg = ("%r already exists in %s; build directory %s will not be "
+                   "kept")
+            log.warn(msg, spec.key, self.build_directory, setup_base)
+            return setup_base
+        if os.path.isdir(dist_filename):
+            setup_base = dist_filename
+        else:
+            if os.path.dirname(dist_filename) == setup_base:
+                os.unlink(dist_filename)  # get it out of the tmp dir
+            contents = os.listdir(setup_base)
+            if len(contents) == 1:
+                dist_filename = os.path.join(setup_base, contents[0])
+                if os.path.isdir(dist_filename):
+                    # if the only thing there is a directory, move it instead
+                    setup_base = dist_filename
+        ensure_directory(dst)
+        shutil.move(setup_base, dst)
+        return dst
+
+    def install_wrapper_scripts(self, dist):
+        if not self.exclude_scripts:
+            for args in get_script_args(dist):
+                self.write_script(*args)
+
+    def install_script(self, dist, script_name, script_text, dev_path=None):
+        """Generate a legacy script wrapper and install it"""
+        spec = str(dist.as_requirement())
+        is_script = is_python_script(script_text, script_name)
+
+        if is_script:
+            script_text = (get_script_header(script_text) +
+                           self._load_template(dev_path) % locals())
+        self.write_script(script_name, _to_ascii(script_text), 'b')
+
+    @staticmethod
+    def _load_template(dev_path):
+        """
+        There are a couple of template scripts in the package. This
+        function loads one of them and prepares it for use.
+        """
+        # See https://bitbucket.org/pypa/setuptools/issue/134 for info
+        # on script file naming and downstream issues with SVR4
+        name = 'script.tmpl'
+        if dev_path:
+            name = name.replace('.tmpl', ' (dev).tmpl')
+
+        raw_bytes = resource_string('setuptools', name)
+        return raw_bytes.decode('utf-8')
+
+    def write_script(self, script_name, contents, mode="t", blockers=()):
+        """Write an executable file to the scripts directory"""
+        self.delete_blockers(  # clean up old .py/.pyw w/o a script
+            [os.path.join(self.script_dir, x) for x in blockers]
+        )
+        log.info("Installing %s script to %s", script_name, self.script_dir)
+        target = os.path.join(self.script_dir, script_name)
+        self.add_output(target)
+
+        mask = current_umask()
+        if not self.dry_run:
+            ensure_directory(target)
+            if os.path.exists(target):
+                os.unlink(target)
+            f = open(target, "w" + mode)
+            f.write(contents)
+            f.close()
+            chmod(target, 0o777 - mask)
+
+    def install_eggs(self, spec, dist_filename, tmpdir):
+        # .egg dirs or files are already built, so just return them
+        if dist_filename.lower().endswith('.egg'):
+            return [self.install_egg(dist_filename, tmpdir)]
+        elif dist_filename.lower().endswith('.exe'):
+            return [self.install_exe(dist_filename, tmpdir)]
+
+        # Anything else, try to extract and build
+        setup_base = tmpdir
+        if os.path.isfile(dist_filename) and not dist_filename.endswith('.py'):
+            unpack_archive(dist_filename, tmpdir, self.unpack_progress)
+        elif os.path.isdir(dist_filename):
+            setup_base = os.path.abspath(dist_filename)
+
+        if (setup_base.startswith(tmpdir)  # something we downloaded
+                and self.build_directory and spec is not None):
+            setup_base = self.maybe_move(spec, dist_filename, setup_base)
+
+        # Find the setup.py file
+        setup_script = os.path.join(setup_base, 'setup.py')
+
+        if not os.path.exists(setup_script):
+            setups = glob(os.path.join(setup_base, '*', 'setup.py'))
+            if not setups:
+                raise DistutilsError(
+                    "Couldn't find a setup script in %s" %
+                    os.path.abspath(dist_filename)
+                )
+            if len(setups) > 1:
+                raise DistutilsError(
+                    "Multiple setup scripts in %s" %
+                    os.path.abspath(dist_filename)
+                )
+            setup_script = setups[0]
+
+        # Now run it, and return the result
+        if self.editable:
+            log.info(self.report_editable(spec, setup_script))
+            return []
+        else:
+            return self.build_and_install(setup_script, setup_base)
+
+    def egg_distribution(self, egg_path):
+        if os.path.isdir(egg_path):
+            metadata = PathMetadata(egg_path, os.path.join(egg_path,
+                                                           'EGG-INFO'))
+        else:
+            metadata = EggMetadata(zipimport.zipimporter(egg_path))
+        return Distribution.from_filename(egg_path, metadata=metadata)
+
+    def install_egg(self, egg_path, tmpdir):
+        destination = os.path.join(self.install_dir,
+                                   os.path.basename(egg_path))
+        destination = os.path.abspath(destination)
+        if not self.dry_run:
+            ensure_directory(destination)
+
+        dist = self.egg_distribution(egg_path)
+        if not samefile(egg_path, destination):
+            if os.path.isdir(destination) and not os.path.islink(destination):
+                dir_util.remove_tree(destination, dry_run=self.dry_run)
+            elif os.path.exists(destination):
+                self.execute(os.unlink, (destination,), "Removing " +
+                             destination)
+            try:
+                new_dist_is_zipped = False
+                if os.path.isdir(egg_path):
+                    if egg_path.startswith(tmpdir):
+                        f, m = shutil.move, "Moving"
+                    else:
+                        f, m = shutil.copytree, "Copying"
+                elif self.should_unzip(dist):
+                    self.mkpath(destination)
+                    f, m = self.unpack_and_compile, "Extracting"
+                else:
+                    new_dist_is_zipped = True
+                    if egg_path.startswith(tmpdir):
+                        f, m = shutil.move, "Moving"
+                    else:
+                        f, m = shutil.copy2, "Copying"
+                self.execute(f, (egg_path, destination),
+                             (m + " %s to %s") %
+                             (os.path.basename(egg_path),
+                              os.path.dirname(destination)))
+                update_dist_caches(destination,
+                                   fix_zipimporter_caches=new_dist_is_zipped)
+            except:
+                update_dist_caches(destination, fix_zipimporter_caches=False)
+                raise
+
+        self.add_output(destination)
+        return self.egg_distribution(destination)
+
+    def install_exe(self, dist_filename, tmpdir):
+        # See if it's valid, get data
+        cfg = extract_wininst_cfg(dist_filename)
+        if cfg is None:
+            raise DistutilsError(
+                "%s is not a valid distutils Windows .exe" % dist_filename
+            )
+        # Create a dummy distribution object until we build the real distro
+        dist = Distribution(
+            None,
+            project_name=cfg.get('metadata', 'name'),
+            version=cfg.get('metadata', 'version'), platform=get_platform(),
+        )
+
+        # Convert the .exe to an unpacked egg
+        egg_path = dist.location = os.path.join(tmpdir, dist.egg_name() +
+                                                '.egg')
+        egg_tmp = egg_path + '.tmp'
+        _egg_info = os.path.join(egg_tmp, 'EGG-INFO')
+        pkg_inf = os.path.join(_egg_info, 'PKG-INFO')
+        ensure_directory(pkg_inf)  # make sure EGG-INFO dir exists
+        dist._provider = PathMetadata(egg_tmp, _egg_info)  # XXX
+        self.exe_to_egg(dist_filename, egg_tmp)
+
+        # Write EGG-INFO/PKG-INFO
+        if not os.path.exists(pkg_inf):
+            f = open(pkg_inf, 'w')
+            f.write('Metadata-Version: 1.0\n')
+            for k, v in cfg.items('metadata'):
+                if k != 'target_version':
+                    f.write('%s: %s\n' % (k.replace('_', '-').title(), v))
+            f.close()
+        script_dir = os.path.join(_egg_info, 'scripts')
+        self.delete_blockers(  # delete entry-point scripts to avoid duping
+            [os.path.join(script_dir, args[0]) for args in
+             get_script_args(dist)]
+        )
+        # Build .egg file from tmpdir
+        bdist_egg.make_zipfile(
+            egg_path, egg_tmp, verbose=self.verbose, dry_run=self.dry_run
+        )
+        # install the .egg
+        return self.install_egg(egg_path, tmpdir)
+
+    def exe_to_egg(self, dist_filename, egg_tmp):
+        """Extract a bdist_wininst to the directories an egg would use"""
+        # Check for .pth file and set up prefix translations
+        prefixes = get_exe_prefixes(dist_filename)
+        to_compile = []
+        native_libs = []
+        top_level = {}
+
+        def process(src, dst):
+            s = src.lower()
+            for old, new in prefixes:
+                if s.startswith(old):
+                    src = new + src[len(old):]
+                    parts = src.split('/')
+                    dst = os.path.join(egg_tmp, *parts)
+                    dl = dst.lower()
+                    if dl.endswith('.pyd') or dl.endswith('.dll'):
+                        parts[-1] = bdist_egg.strip_module(parts[-1])
+                        top_level[os.path.splitext(parts[0])[0]] = 1
+                        native_libs.append(src)
+                    elif dl.endswith('.py') and old != 'SCRIPTS/':
+                        top_level[os.path.splitext(parts[0])[0]] = 1
+                        to_compile.append(dst)
+                    return dst
+            if not src.endswith('.pth'):
+                log.warn("WARNING: can't process %s", src)
+            return None
+
+        # extract, tracking .pyd/.dll->native_libs and .py -> to_compile
+        unpack_archive(dist_filename, egg_tmp, process)
+        stubs = []
+        for res in native_libs:
+            if res.lower().endswith('.pyd'):  # create stubs for .pyd's
+                parts = res.split('/')
+                resource = parts[-1]
+                parts[-1] = bdist_egg.strip_module(parts[-1]) + '.py'
+                pyfile = os.path.join(egg_tmp, *parts)
+                to_compile.append(pyfile)
+                stubs.append(pyfile)
+                bdist_egg.write_stub(resource, pyfile)
+        self.byte_compile(to_compile)  # compile .py's
+        bdist_egg.write_safety_flag(
+            os.path.join(egg_tmp, 'EGG-INFO'),
+            bdist_egg.analyze_egg(egg_tmp, stubs))  # write zip-safety flag
+
+        for name in 'top_level', 'native_libs':
+            if locals()[name]:
+                txt = os.path.join(egg_tmp, 'EGG-INFO', name + '.txt')
+                if not os.path.exists(txt):
+                    f = open(txt, 'w')
+                    f.write('\n'.join(locals()[name]) + '\n')
+                    f.close()
+
+    def installation_report(self, req, dist, what="Installed"):
+        """Helpful installation message for display to package users"""
+        msg = "\n%(what)s %(eggloc)s%(extras)s"
+        if self.multi_version and not self.no_report:
+            msg += """
+
+Because this distribution was installed --multi-version, before you can
+import modules from this package in an application, you will need to
+'import pkg_resources' and then use a 'require()' call similar to one of
+these examples, in order to select the desired version:
+
+    pkg_resources.require("%(name)s")  # latest installed version
+    pkg_resources.require("%(name)s==%(version)s")  # this exact version
+    pkg_resources.require("%(name)s>=%(version)s")  # this version or higher
+"""
+            if self.install_dir not in map(normalize_path, sys.path):
+                msg += """
+
+Note also that the installation directory must be on sys.path at runtime for
+this to work.  (e.g. by being the application's script directory, by being on
+PYTHONPATH, or by being added to sys.path by your code.)
+"""
+        eggloc = dist.location
+        name = dist.project_name
+        version = dist.version
+        extras = ''  # TODO: self.report_extras(req, dist)
+        return msg % locals()
+
+    def report_editable(self, spec, setup_script):
+        dirname = os.path.dirname(setup_script)
+        python = sys.executable
+        return """\nExtracted editable version of %(spec)s to %(dirname)s
+
+If it uses setuptools in its setup script, you can activate it in
+"development" mode by going to that directory and running::
+
+    %(python)s setup.py develop
+
+See the setuptools documentation for the "develop" command for more info.
+""" % locals()
+
+    def run_setup(self, setup_script, setup_base, args):
+        sys.modules.setdefault('distutils.command.bdist_egg', bdist_egg)
+        sys.modules.setdefault('distutils.command.egg_info', egg_info)
+
+        args = list(args)
+        if self.verbose > 2:
+            v = 'v' * (self.verbose - 1)
+            args.insert(0, '-' + v)
+        elif self.verbose < 2:
+            args.insert(0, '-q')
+        if self.dry_run:
+            args.insert(0, '-n')
+        log.info(
+            "Running %s %s", setup_script[len(setup_base) + 1:], ' '.join(args)
+        )
+        try:
+            run_setup(setup_script, args)
+        except SystemExit:
+            v = sys.exc_info()[1]
+            raise DistutilsError("Setup script exited with %s" % (v.args[0],))
+
+    def build_and_install(self, setup_script, setup_base):
+        args = ['bdist_egg', '--dist-dir']
+
+        dist_dir = tempfile.mkdtemp(
+            prefix='egg-dist-tmp-', dir=os.path.dirname(setup_script)
+        )
+        try:
+            self._set_fetcher_options(os.path.dirname(setup_script))
+            args.append(dist_dir)
+
+            self.run_setup(setup_script, setup_base, args)
+            all_eggs = Environment([dist_dir])
+            eggs = []
+            for key in all_eggs:
+                for dist in all_eggs[key]:
+                    eggs.append(self.install_egg(dist.location, setup_base))
+            if not eggs and not self.dry_run:
+                log.warn("No eggs found in %s (setup script problem?)",
+                         dist_dir)
+            return eggs
+        finally:
+            rmtree(dist_dir)
+            log.set_verbosity(self.verbose)  # restore our log verbosity
+
+    def _set_fetcher_options(self, base):
+        """
+        When easy_install is about to run bdist_egg on a source dist, that
+        source dist might have 'setup_requires' directives, requiring
+        additional fetching. Ensure the fetcher options given to easy_install
+        are available to that command as well.
+        """
+        # find the fetch options from easy_install and write them out
+        # to the setup.cfg file.
+        ei_opts = self.distribution.get_option_dict('easy_install').copy()
+        fetch_directives = (
+            'find_links', 'site_dirs', 'index_url', 'optimize',
+            'site_dirs', 'allow_hosts',
+        )
+        fetch_options = {}
+        for key, val in ei_opts.items():
+            if key not in fetch_directives:
+                continue
+            fetch_options[key.replace('_', '-')] = val[1]
+        # create a settings dictionary suitable for `edit_config`
+        settings = dict(easy_install=fetch_options)
+        cfg_filename = os.path.join(base, 'setup.cfg')
+        setopt.edit_config(cfg_filename, settings)
+
+    def update_pth(self, dist):
+        if self.pth_file is None:
+            return
+
+        for d in self.pth_file[dist.key]:  # drop old entries
+            if self.multi_version or d.location != dist.location:
+                log.info("Removing %s from easy-install.pth file", d)
+                self.pth_file.remove(d)
+                if d.location in self.shadow_path:
+                    self.shadow_path.remove(d.location)
+
+        if not self.multi_version:
+            if dist.location in self.pth_file.paths:
+                log.info(
+                    "%s is already the active version in easy-install.pth",
+                    dist
+                )
+            else:
+                log.info("Adding %s to easy-install.pth file", dist)
+                self.pth_file.add(dist)  # add new entry
+                if dist.location not in self.shadow_path:
+                    self.shadow_path.append(dist.location)
+
+        if not self.dry_run:
+
+            self.pth_file.save()
+
+            if dist.key == 'setuptools':
+                # Ensure that setuptools itself never becomes unavailable!
+                # XXX should this check for latest version?
+                filename = os.path.join(self.install_dir, 'setuptools.pth')
+                if os.path.islink(filename):
+                    os.unlink(filename)
+                f = open(filename, 'wt')
+                f.write(self.pth_file.make_relative(dist.location) + '\n')
+                f.close()
+
+    def unpack_progress(self, src, dst):
+        # Progress filter for unpacking
+        log.debug("Unpacking %s to %s", src, dst)
+        return dst  # only unpack-and-compile skips files for dry run
+
+    def unpack_and_compile(self, egg_path, destination):
+        to_compile = []
+        to_chmod = []
+
+        def pf(src, dst):
+            if dst.endswith('.py') and not src.startswith('EGG-INFO/'):
+                to_compile.append(dst)
+            elif dst.endswith('.dll') or dst.endswith('.so'):
+                to_chmod.append(dst)
+            self.unpack_progress(src, dst)
+            return not self.dry_run and dst or None
+
+        unpack_archive(egg_path, destination, pf)
+        self.byte_compile(to_compile)
+        if not self.dry_run:
+            for f in to_chmod:
+                mode = ((os.stat(f)[stat.ST_MODE]) | 0o555) & 0o7755
+                chmod(f, mode)
+
+    def byte_compile(self, to_compile):
+        if sys.dont_write_bytecode:
+            self.warn('byte-compiling is disabled, skipping.')
+            return
+
+        from distutils.util import byte_compile
+
+        try:
+            # try to make the byte compile messages quieter
+            log.set_verbosity(self.verbose - 1)
+
+            byte_compile(to_compile, optimize=0, force=1, dry_run=self.dry_run)
+            if self.optimize:
+                byte_compile(
+                    to_compile, optimize=self.optimize, force=1,
+                    dry_run=self.dry_run
+                )
+        finally:
+            log.set_verbosity(self.verbose)  # restore original verbosity
+
+    def no_default_version_msg(self):
+        template = """bad install directory or PYTHONPATH
+
+You are attempting to install a package to a directory that is not
+on PYTHONPATH and which Python does not read ".pth" files from.  The
+installation directory you specified (via --install-dir, --prefix, or
+the distutils default setting) was:
+
+    %s
+
+and your PYTHONPATH environment variable currently contains:
+
+    %r
+
+Here are some of your options for correcting the problem:
+
+* You can choose a different installation directory, i.e., one that is
+  on PYTHONPATH or supports .pth files
+
+* You can add the installation directory to the PYTHONPATH environment
+  variable.  (It must then also be on PYTHONPATH whenever you run
+  Python and want to use the package(s) you are installing.)
+
+* You can set up the installation directory to support ".pth" files by
+  using one of the approaches described here:
+
+  https://pythonhosted.org/setuptools/easy_install.html#custom-installation-locations
+
+Please make the appropriate changes for your system and try again."""
+        return template % (self.install_dir, os.environ.get('PYTHONPATH', ''))
+
+    def install_site_py(self):
+        """Make sure there's a site.py in the target dir, if needed"""
+
+        if self.sitepy_installed:
+            return  # already did it, or don't need to
+
+        sitepy = os.path.join(self.install_dir, "site.py")
+        source = resource_string("setuptools", "site-patch.py")
+        current = ""
+
+        if os.path.exists(sitepy):
+            log.debug("Checking existing site.py in %s", self.install_dir)
+            f = open(sitepy, 'rb')
+            current = f.read()
+            # we want str, not bytes
+            if PY3:
+                current = current.decode()
+
+            f.close()
+            if not current.startswith('def __boot():'):
+                raise DistutilsError(
+                    "%s is not a setuptools-generated site.py; please"
+                    " remove it." % sitepy
+                )
+
+        if current != source:
+            log.info("Creating %s", sitepy)
+            if not self.dry_run:
+                ensure_directory(sitepy)
+                f = open(sitepy, 'wb')
+                f.write(source)
+                f.close()
+            self.byte_compile([sitepy])
+
+        self.sitepy_installed = True
+
+    def create_home_path(self):
+        """Create directories under ~."""
+        if not self.user:
+            return
+        home = convert_path(os.path.expanduser("~"))
+        for name, path in iteritems(self.config_vars):
+            if path.startswith(home) and not os.path.isdir(path):
+                self.debug_print("os.makedirs('%s', 0o700)" % path)
+                os.makedirs(path, 0o700)
+
+    INSTALL_SCHEMES = dict(
+        posix=dict(
+            install_dir='$base/lib/python$py_version_short/site-packages',
+            script_dir='$base/bin',
+        ),
+    )
+
+    DEFAULT_SCHEME = dict(
+        install_dir='$base/Lib/site-packages',
+        script_dir='$base/Scripts',
+    )
+
+    def _expand(self, *attrs):
+        config_vars = self.get_finalized_command('install').config_vars
+
+        if self.prefix:
+            # Set default install_dir/scripts from --prefix
+            config_vars = config_vars.copy()
+            config_vars['base'] = self.prefix
+            scheme = self.INSTALL_SCHEMES.get(os.name, self.DEFAULT_SCHEME)
+            for attr, val in scheme.items():
+                if getattr(self, attr, None) is None:
+                    setattr(self, attr, val)
+
+        from distutils.util import subst_vars
+
+        for attr in attrs:
+            val = getattr(self, attr)
+            if val is not None:
+                val = subst_vars(val, config_vars)
+                if os.name == 'posix':
+                    val = os.path.expanduser(val)
+                setattr(self, attr, val)
+
+
+def get_site_dirs():
+    # return a list of 'site' dirs
+    sitedirs = [_f for _f in os.environ.get('PYTHONPATH',
+                                            '').split(os.pathsep) if _f]
+    prefixes = [sys.prefix]
+    if sys.exec_prefix != sys.prefix:
+        prefixes.append(sys.exec_prefix)
+    for prefix in prefixes:
+        if prefix:
+            if sys.platform in ('os2emx', 'riscos'):
+                sitedirs.append(os.path.join(prefix, "Lib", "site-packages"))
+            elif os.sep == '/':
+                sitedirs.extend([os.path.join(prefix,
+                                              "lib",
+                                              "python" + sys.version[:3],
+                                              "site-packages"),
+                                 os.path.join(prefix, "lib", "site-python")])
+            else:
+                sitedirs.extend(
+                    [prefix, os.path.join(prefix, "lib", "site-packages")]
+                )
+            if sys.platform == 'darwin':
+                # for framework builds *only* we add the standard Apple
+                # locations. Currently only per-user, but /Library and
+                # /Network/Library could be added too
+                if 'Python.framework' in prefix:
+                    home = os.environ.get('HOME')
+                    if home:
+                        sitedirs.append(
+                            os.path.join(home,
+                                         'Library',
+                                         'Python',
+                                         sys.version[:3],
+                                         'site-packages'))
+    lib_paths = get_path('purelib'), get_path('platlib')
+    for site_lib in lib_paths:
+        if site_lib not in sitedirs:
+            sitedirs.append(site_lib)
+
+    if site.ENABLE_USER_SITE:
+        sitedirs.append(site.USER_SITE)
+
+    sitedirs = list(map(normalize_path, sitedirs))
+
+    return sitedirs
+
+
+def expand_paths(inputs):
+    """Yield sys.path directories that might contain "old-style" packages"""
+
+    seen = {}
+
+    for dirname in inputs:
+        dirname = normalize_path(dirname)
+        if dirname in seen:
+            continue
+
+        seen[dirname] = 1
+        if not os.path.isdir(dirname):
+            continue
+
+        files = os.listdir(dirname)
+        yield dirname, files
+
+        for name in files:
+            if not name.endswith('.pth'):
+                # We only care about the .pth files
+                continue
+            if name in ('easy-install.pth', 'setuptools.pth'):
+                # Ignore .pth files that we control
+                continue
+
+            # Read the .pth file
+            f = open(os.path.join(dirname, name))
+            lines = list(yield_lines(f))
+            f.close()
+
+            # Yield existing non-dupe, non-import directory lines from it
+            for line in lines:
+                if not line.startswith("import"):
+                    line = normalize_path(line.rstrip())
+                    if line not in seen:
+                        seen[line] = 1
+                        if not os.path.isdir(line):
+                            continue
+                        yield line, os.listdir(line)
+
+
+def extract_wininst_cfg(dist_filename):
+    """Extract configuration data from a bdist_wininst .exe
+
+    Returns a ConfigParser.RawConfigParser, or None
+    """
+    f = open(dist_filename, 'rb')
+    try:
+        endrec = zipfile._EndRecData(f)
+        if endrec is None:
+            return None
+
+        prepended = (endrec[9] - endrec[5]) - endrec[6]
+        if prepended < 12:  # no wininst data here
+            return None
+        f.seek(prepended - 12)
+
+        from setuptools.compat import StringIO, ConfigParser
+        import struct
+
+        tag, cfglen, bmlen = struct.unpack("<iii", f.read(12))
+        if tag not in (0x1234567A, 0x1234567B):
+            return None  # not a valid tag
+
+        f.seek(prepended - (12 + cfglen))
+        cfg = ConfigParser.RawConfigParser(
+            {'version': '', 'target_version': ''})
+        try:
+            part = f.read(cfglen)
+            # part is in bytes, but we need to read up to the first null
+            # byte.
+            if sys.version_info >= (2, 6):
+                null_byte = bytes([0])
+            else:
+                null_byte = chr(0)
+            config = part.split(null_byte, 1)[0]
+            # Now the config is in bytes, but for RawConfigParser, it should
+            #  be text, so decode it.
+            config = config.decode(sys.getfilesystemencoding())
+            cfg.readfp(StringIO(config))
+        except ConfigParser.Error:
+            return None
+        if not cfg.has_section('metadata') or not cfg.has_section('Setup'):
+            return None
+        return cfg
+
+    finally:
+        f.close()
+
+
+def get_exe_prefixes(exe_filename):
+    """Get exe->egg path translations for a given .exe file"""
+
+    prefixes = [
+        ('PURELIB/', ''), ('PLATLIB/pywin32_system32', ''),
+        ('PLATLIB/', ''),
+        ('SCRIPTS/', 'EGG-INFO/scripts/'),
+        ('DATA/lib/site-packages', ''),
+    ]
+    z = zipfile.ZipFile(exe_filename)
+    try:
+        for info in z.infolist():
+            name = info.filename
+            parts = name.split('/')
+            if len(parts) == 3 and parts[2] == 'PKG-INFO':
+                if parts[1].endswith('.egg-info'):
+                    prefixes.insert(0, ('/'.join(parts[:2]), 'EGG-INFO/'))
+                    break
+            if len(parts) != 2 or not name.endswith('.pth'):
+                continue
+            if name.endswith('-nspkg.pth'):
+                continue
+            if parts[0].upper() in ('PURELIB', 'PLATLIB'):
+                contents = z.read(name)
+                if PY3:
+                    contents = contents.decode()
+                for pth in yield_lines(contents):
+                    pth = pth.strip().replace('\\', '/')
+                    if not pth.startswith('import'):
+                        prefixes.append((('%s/%s/' % (parts[0], pth)), ''))
+    finally:
+        z.close()
+    prefixes = [(x.lower(), y) for x, y in prefixes]
+    prefixes.sort()
+    prefixes.reverse()
+    return prefixes
+
+
+def parse_requirement_arg(spec):
+    try:
+        return Requirement.parse(spec)
+    except ValueError:
+        raise DistutilsError(
+            "Not a URL, existing file, or requirement spec: %r" % (spec,)
+        )
+
+
+class PthDistributions(Environment):
+    """A .pth file with Distribution paths in it"""
+
+    dirty = False
+
+    def __init__(self, filename, sitedirs=()):
+        self.filename = filename
+        self.sitedirs = list(map(normalize_path, sitedirs))
+        self.basedir = normalize_path(os.path.dirname(self.filename))
+        self._load()
+        Environment.__init__(self, [], None, None)
+        for path in yield_lines(self.paths):
+            list(map(self.add, find_distributions(path, True)))
+
+    def _load(self):
+        self.paths = []
+        saw_import = False
+        seen = dict.fromkeys(self.sitedirs)
+        if os.path.isfile(self.filename):
+            f = open(self.filename, 'rt')
+            for line in f:
+                if line.startswith('import'):
+                    saw_import = True
+                    continue
+                path = line.rstrip()
+                self.paths.append(path)
+                if not path.strip() or path.strip().startswith('#'):
+                    continue
+                # skip non-existent paths, in case somebody deleted a package
+                # manually, and duplicate paths as well
+                path = self.paths[-1] = normalize_path(
+                    os.path.join(self.basedir, path)
+                )
+                if not os.path.exists(path) or path in seen:
+                    self.paths.pop()  # skip it
+                    self.dirty = True  # we cleaned up, so we're dirty now :)
+                    continue
+                seen[path] = 1
+            f.close()
+
+        if self.paths and not saw_import:
+            self.dirty = True  # ensure anything we touch has import wrappers
+        while self.paths and not self.paths[-1].strip():
+            self.paths.pop()
+
+    def save(self):
+        """Write changed .pth file back to disk"""
+        if not self.dirty:
+            return
+
+        data = '\n'.join(map(self.make_relative, self.paths))
+        if data:
+            log.debug("Saving %s", self.filename)
+            data = (
+                "import sys; sys.__plen = len(sys.path)\n"
+                "%s\n"
+                "import sys; new=sys.path[sys.__plen:];"
+                " del sys.path[sys.__plen:];"
+                " p=getattr(sys,'__egginsert',0); sys.path[p:p]=new;"
+                " sys.__egginsert = p+len(new)\n"
+            ) % data
+
+            if os.path.islink(self.filename):
+                os.unlink(self.filename)
+            f = open(self.filename, 'wt')
+            f.write(data)
+            f.close()
+
+        elif os.path.exists(self.filename):
+            log.debug("Deleting empty %s", self.filename)
+            os.unlink(self.filename)
+
+        self.dirty = False
+
+    def add(self, dist):
+        """Add `dist` to the distribution map"""
+        if (dist.location not in self.paths and (
+            dist.location not in self.sitedirs or
+            dist.location == os.getcwd()  # account for '.' being in PYTHONPATH
+        )):
+            self.paths.append(dist.location)
+            self.dirty = True
+        Environment.add(self, dist)
+
+    def remove(self, dist):
+        """Remove `dist` from the distribution map"""
+        while dist.location in self.paths:
+            self.paths.remove(dist.location)
+            self.dirty = True
+        Environment.remove(self, dist)
+
+    def make_relative(self, path):
+        npath, last = os.path.split(normalize_path(path))
+        baselen = len(self.basedir)
+        parts = [last]
+        sep = os.altsep == '/' and '/' or os.sep
+        while len(npath) >= baselen:
+            if npath == self.basedir:
+                parts.append(os.curdir)
+                parts.reverse()
+                return sep.join(parts)
+            npath, last = os.path.split(npath)
+            parts.append(last)
+        else:
+            return path
+
+
+def _first_line_re():
+    """
+    Return a regular expression based on first_line_re suitable for matching
+    strings.
+    """
+    if isinstance(first_line_re.pattern, str):
+        return first_line_re
+
+    # first_line_re in Python >=3.1.4 and >=3.2.1 is a bytes pattern.
+    return re.compile(first_line_re.pattern.decode())
+
+
+def get_script_header(script_text, executable=sys_executable, wininst=False):
+    """Create a #! line, getting options (if any) from script_text"""
+    first = (script_text + '\n').splitlines()[0]
+    match = _first_line_re().match(first)
+    options = ''
+    if match:
+        options = match.group(1) or ''
+        if options:
+            options = ' ' + options
+    if wininst:
+        executable = "python.exe"
+    else:
+        executable = nt_quote_arg(executable)
+    hdr = "#!%(executable)s%(options)s\n" % locals()
+    if not isascii(hdr):
+        # Non-ascii path to sys.executable, use -x to prevent warnings
+        if options:
+            if options.strip().startswith('-'):
+                options = ' -x' + options.strip()[1:]
+                # else: punt, we can't do it, let the warning happen anyway
+        else:
+            options = ' -x'
+    executable = fix_jython_executable(executable, options)
+    hdr = "#!%(executable)s%(options)s\n" % locals()
+    return hdr
+
+
+def auto_chmod(func, arg, exc):
+    if func is os.remove and os.name == 'nt':
+        chmod(arg, stat.S_IWRITE)
+        return func(arg)
+    et, ev, _ = sys.exc_info()
+    reraise(et, (ev[0], ev[1] + (" %s %s" % (func, arg))))
+
+
+def update_dist_caches(dist_path, fix_zipimporter_caches):
+    """
+    Fix any globally cached `dist_path` related data
+
+    `dist_path` should be a path of a newly installed egg distribution (zipped
+    or unzipped).
+
+    sys.path_importer_cache contains finder objects that have been cached when
+    importing data from the original distribution. Any such finders need to be
+    cleared since the replacement distribution might be packaged differently,
+    e.g. a zipped egg distribution might get replaced with an unzipped egg
+    folder or vice versa. Having the old finders cached may then cause Python
+    to attempt loading modules from the replacement distribution using an
+    incorrect loader.
+
+    zipimport.zipimporter objects are Python loaders charged with importing
+    data packaged inside zip archives. If stale loaders referencing the
+    original distribution, are left behind, they can fail to load modules from
+    the replacement distribution. E.g. if an old zipimport.zipimporter instance
+    is used to load data from a new zipped egg archive, it may cause the
+    operation to attempt to locate the requested data in the wrong location -
+    one indicated by the original distribution's zip archive directory
+    information. Such an operation may then fail outright, e.g. report having
+    read a 'bad local file header', or even worse, it may fail silently &
+    return invalid data.
+
+    zipimport._zip_directory_cache contains cached zip archive directory
+    information for all existing zipimport.zipimporter instances and all such
+    instances connected to the same archive share the same cached directory
+    information.
+
+    If asked, and the underlying Python implementation allows it, we can fix
+    all existing zipimport.zipimporter instances instead of having to track
+    them down and remove them one by one, by updating their shared cached zip
+    archive directory information. This, of course, assumes that the
+    replacement distribution is packaged as a zipped egg.
+
+    If not asked to fix existing zipimport.zipimporter instances, we still do
+    our best to clear any remaining zipimport.zipimporter related cached data
+    that might somehow later get used when attempting to load data from the new
+    distribution and thus cause such load operations to fail. Note that when
+    tracking down such remaining stale data, we can not catch every conceivable
+    usage from here, and we clear only those that we know of and have found to
+    cause problems if left alive. Any remaining caches should be updated by
+    whomever is in charge of maintaining them, i.e. they should be ready to
+    handle us replacing their zip archives with new distributions at runtime.
+
+    """
+    # There are several other known sources of stale zipimport.zipimporter
+    # instances that we do not clear here, but might if ever given a reason to
+    # do so:
+    # * Global setuptools pkg_resources.working_set (a.k.a. 'master working
+    # set') may contain distributions which may in turn contain their
+    #   zipimport.zipimporter loaders.
+    # * Several zipimport.zipimporter loaders held by local variables further
+    #   up the function call stack when running the setuptools installation.
+    # * Already loaded modules may have their __loader__ attribute set to the
+    #   exact loader instance used when importing them. Python 3.4 docs state
+    #   that this information is intended mostly for introspection and so is
+    #   not expected to cause us problems.
+    normalized_path = normalize_path(dist_path)
+    _uncache(normalized_path, sys.path_importer_cache)
+    if fix_zipimporter_caches:
+        _replace_zip_directory_cache_data(normalized_path)
+    else:
+        # Here, even though we do not want to fix existing and now stale
+        # zipimporter cache information, we still want to remove it. Related to
+        # Python's zip archive directory information cache, we clear each of
+        # its stale entries in two phases:
+        #   1. Clear the entry so attempting to access zip archive information
+        #      via any existing stale zipimport.zipimporter instances fails.
+        #   2. Remove the entry from the cache so any newly constructed
+        #      zipimport.zipimporter instances do not end up using old stale
+        #      zip archive directory information.
+        # This whole stale data removal step does not seem strictly necessary,
+        # but has been left in because it was done before we started replacing
+        # the zip archive directory information cache content if possible, and
+        # there are no relevant unit tests that we can depend on to tell us if
+        # this is really needed.
+        _remove_and_clear_zip_directory_cache_data(normalized_path)
+
+
+def _collect_zipimporter_cache_entries(normalized_path, cache):
+    """
+    Return zipimporter cache entry keys related to a given normalized path.
+
+    Alternative path spellings (e.g. those using different character case or
+    those using alternative path separators) related to the same path are
+    included. Any sub-path entries are included as well, i.e. those
+    corresponding to zip archives embedded in other zip archives.
+
+    """
+    result = []
+    prefix_len = len(normalized_path)
+    for p in cache:
+        np = normalize_path(p)
+        if (np.startswith(normalized_path) and
+                np[prefix_len:prefix_len + 1] in (os.sep, '')):
+            result.append(p)
+    return result
+
+
+def _update_zipimporter_cache(normalized_path, cache, updater=None):
+    """
+    Update zipimporter cache data for a given normalized path.
+
+    Any sub-path entries are processed as well, i.e. those corresponding to zip
+    archives embedded in other zip archives.
+
+    Given updater is a callable taking a cache entry key and the original entry
+    (after already removing the entry from the cache), and expected to update
+    the entry and possibly return a new one to be inserted in its place.
+    Returning None indicates that the entry should not be replaced with a new
+    one. If no updater is given, the cache entries are simply removed without
+    any additional processing, the same as if the updater simply returned None.
+
+    """
+    for p in _collect_zipimporter_cache_entries(normalized_path, cache):
+        # N.B. pypy's custom zipimport._zip_directory_cache implementation does
+        # not support the complete dict interface:
+        # * Does not support item assignment, thus not allowing this function
+        #    to be used only for removing existing cache entries.
+        #  * Does not support the dict.pop() method, forcing us to use the
+        #    get/del patterns instead. For more detailed information see the
+        #    following links:
+        #      https://bitbucket.org/pypa/setuptools/issue/202/more-robust-zipimporter-cache-invalidation#comment-10495960
+        #      https://bitbucket.org/pypy/pypy/src/dd07756a34a41f674c0cacfbc8ae1d4cc9ea2ae4/pypy/module/zipimport/interp_zipimport.py#cl-99
+        old_entry = cache[p]
+        del cache[p]
+        new_entry = updater and updater(p, old_entry)
+        if new_entry is not None:
+            cache[p] = new_entry
+
+
+def _uncache(normalized_path, cache):
+    _update_zipimporter_cache(normalized_path, cache)
+
+
+def _remove_and_clear_zip_directory_cache_data(normalized_path):
+    def clear_and_remove_cached_zip_archive_directory_data(path, old_entry):
+        old_entry.clear()
+
+    _update_zipimporter_cache(
+        normalized_path, zipimport._zip_directory_cache,
+        updater=clear_and_remove_cached_zip_archive_directory_data)
+
+# PyPy Python implementation does not allow directly writing to the
+# zipimport._zip_directory_cache and so prevents us from attempting to correct
+# its content. The best we can do there is clear the problematic cache content
+# and have PyPy repopulate it as needed. The downside is that if there are any
+# stale zipimport.zipimporter instances laying around, attempting to use them
+# will fail due to not having its zip archive directory information available
+# instead of being automatically corrected to use the new correct zip archive
+# directory information.
+if '__pypy__' in sys.builtin_module_names:
+    _replace_zip_directory_cache_data = \
+        _remove_and_clear_zip_directory_cache_data
+else:
+    def _replace_zip_directory_cache_data(normalized_path):
+        def replace_cached_zip_archive_directory_data(path, old_entry):
+            # N.B. In theory, we could load the zip directory information just
+            # once for all updated path spellings, and then copy it locally and
+            # update its contained path strings to contain the correct
+            # spelling, but that seems like a way too invasive move (this cache
+            # structure is not officially documented anywhere and could in
+            # theory change with new Python releases) for no significant
+            # benefit.
+            old_entry.clear()
+            zipimport.zipimporter(path)
+            old_entry.update(zipimport._zip_directory_cache[path])
+            return old_entry
+
+        _update_zipimporter_cache(
+            normalized_path, zipimport._zip_directory_cache,
+            updater=replace_cached_zip_archive_directory_data)
+
+
+def is_python(text, filename='<string>'):
+    "Is this string a valid Python script?"
+    try:
+        compile(text, filename, 'exec')
+    except (SyntaxError, TypeError):
+        return False
+    else:
+        return True
+
+
+def is_sh(executable):
+    """Determine if the specified executable is a .sh (contains a #! line)"""
+    try:
+        fp = open(executable)
+        magic = fp.read(2)
+        fp.close()
+    except (OSError, IOError):
+        return executable
+    return magic == '#!'
+
+
+def nt_quote_arg(arg):
+    """Quote a command line argument according to Windows parsing rules"""
+
+    result = []
+    needquote = False
+    nb = 0
+
+    needquote = (" " in arg) or ("\t" in arg)
+    if needquote:
+        result.append('"')
+
+    for c in arg:
+        if c == '\\':
+            nb += 1
+        elif c == '"':
+            # double preceding backslashes, then add a \"
+            result.append('\\' * (nb * 2) + '\\"')
+            nb = 0
+        else:
+            if nb:
+                result.append('\\' * nb)
+                nb = 0
+            result.append(c)
+
+    if nb:
+        result.append('\\' * nb)
+
+    if needquote:
+        result.append('\\' * nb)  # double the trailing backslashes
+        result.append('"')
+
+    return ''.join(result)
+
+
+def is_python_script(script_text, filename):
+    """Is this text, as a whole, a Python script? (as opposed to shell/bat/etc.
+    """
+    if filename.endswith('.py') or filename.endswith('.pyw'):
+        return True  # extension says it's Python
+    if is_python(script_text, filename):
+        return True  # it's syntactically valid Python
+    if script_text.startswith('#!'):
+        # It begins with a '#!' line, so check if 'python' is in it somewhere
+        return 'python' in script_text.splitlines()[0].lower()
+
+    return False  # Not any Python I can recognize
+
+
+try:
+    from os import chmod as _chmod
+except ImportError:
+    # Jython compatibility
+    def _chmod(*args):
+        pass
+
+
+def chmod(path, mode):
+    log.debug("changing mode of %s to %o", path, mode)
+    try:
+        _chmod(path, mode)
+    except os.error:
+        e = sys.exc_info()[1]
+        log.debug("chmod failed: %s", e)
+
+
+def fix_jython_executable(executable, options):
+    if sys.platform.startswith('java') and is_sh(executable):
+        # Workaround for Jython is not needed on Linux systems.
+        import java
+
+        if java.lang.System.getProperty("os.name") == "Linux":
+            return executable
+
+        # Workaround Jython's sys.executable being a .sh (an invalid
+        # shebang line interpreter)
+        if options:
+            # Can't apply the workaround, leave it broken
+            log.warn(
+                "WARNING: Unable to adapt shebang line for Jython,"
+                " the following script is NOT executable\n"
+                "         see http://bugs.jython.org/issue1112 for"
+                " more information.")
+        else:
+            return '/usr/bin/env %s' % executable
+    return executable
+
+
+class ScriptWriter(object):
+    """
+    Encapsulates behavior around writing entry point scripts for console and
+    gui apps.
+    """
+
+    template = textwrap.dedent("""
+        # EASY-INSTALL-ENTRY-SCRIPT: %(spec)r,%(group)r,%(name)r
+        __requires__ = %(spec)r
+        import sys
+        from pkg_resources import load_entry_point
+
+        if __name__ == '__main__':
+            sys.exit(
+                load_entry_point(%(spec)r, %(group)r, %(name)r)()
+            )
+    """).lstrip()
+
+    @classmethod
+    def get_script_args(cls, dist, executable=sys_executable, wininst=False):
+        """
+        Yield write_script() argument tuples for a distribution's entrypoints
+        """
+        gen_class = cls.get_writer(wininst)
+        spec = str(dist.as_requirement())
+        header = get_script_header("", executable, wininst)
+        for type_ in 'console', 'gui':
+            group = type_ + '_scripts'
+            for name, ep in dist.get_entry_map(group).items():
+                script_text = gen_class.template % locals()
+                for res in gen_class._get_script_args(type_, name, header,
+                                                      script_text):
+                    yield res
+
+    @classmethod
+    def get_writer(cls, force_windows):
+        if force_windows or sys.platform == 'win32':
+            return WindowsScriptWriter.get_writer()
+        return cls
+
+    @classmethod
+    def _get_script_args(cls, type_, name, header, script_text):
+        # Simply write the stub with no extension.
+        yield (name, header + script_text)
+
+
+class WindowsScriptWriter(ScriptWriter):
+    @classmethod
+    def get_writer(cls):
+        """
+        Get a script writer suitable for Windows
+        """
+        writer_lookup = dict(
+            executable=WindowsExecutableLauncherWriter,
+            natural=cls,
+        )
+        # for compatibility, use the executable launcher by default
+        launcher = os.environ.get('SETUPTOOLS_LAUNCHER', 'executable')
+        return writer_lookup[launcher]
+
+    @classmethod
+    def _get_script_args(cls, type_, name, header, script_text):
+        "For Windows, add a .py extension"
+        ext = dict(console='.pya', gui='.pyw')[type_]
+        if ext not in os.environ['PATHEXT'].lower().split(';'):
+            warnings.warn("%s not listed in PATHEXT; scripts will not be "
+                          "recognized as executables." % ext, UserWarning)
+        old = ['.pya', '.py', '-script.py', '.pyc', '.pyo', '.pyw', '.exe']
+        old.remove(ext)
+        header = cls._adjust_header(type_, header)
+        blockers = [name + x for x in old]
+        yield name + ext, header + script_text, 't', blockers
+
+    @staticmethod
+    def _adjust_header(type_, orig_header):
+        """
+        Make sure 'pythonw' is used for gui and and 'python' is used for
+        console (regardless of what sys.executable is).
+        """
+        pattern = 'pythonw.exe'
+        repl = 'python.exe'
+        if type_ == 'gui':
+            pattern, repl = repl, pattern
+        pattern_ob = re.compile(re.escape(pattern), re.IGNORECASE)
+        new_header = pattern_ob.sub(string=orig_header, repl=repl)
+        clean_header = new_header[2:-1].strip('"')
+        if sys.platform == 'win32' and not os.path.exists(clean_header):
+            # the adjusted version doesn't exist, so return the original
+            return orig_header
+        return new_header
+
+
+class WindowsExecutableLauncherWriter(WindowsScriptWriter):
+    @classmethod
+    def _get_script_args(cls, type_, name, header, script_text):
+        """
+        For Windows, add a .py extension and an .exe launcher
+        """
+        if type_ == 'gui':
+            launcher_type = 'gui'
+            ext = '-script.pyw'
+            old = ['.pyw']
+        else:
+            launcher_type = 'cli'
+            ext = '-script.py'
+            old = ['.py', '.pyc', '.pyo']
+        hdr = cls._adjust_header(type_, header)
+        blockers = [name + x for x in old]
+        yield (name + ext, hdr + script_text, 't', blockers)
+        yield (
+            name + '.exe', get_win_launcher(launcher_type),
+            'b'  # write in binary mode
+        )
+        if not is_64bit():
+            # install a manifest for the launcher to prevent Windows
+            # from detecting it as an installer (which it will for
+            #  launchers like easy_install.exe). Consider only
+            #  adding a manifest for launchers detected as installers.
+            #  See Distribute #143 for details.
+            m_name = name + '.exe.manifest'
+            yield (m_name, load_launcher_manifest(name), 't')
+
+
+# for backward-compatibility
+get_script_args = ScriptWriter.get_script_args
+
+
+def get_win_launcher(type):
+    """
+    Load the Windows launcher (executable) suitable for launching a script.
+
+    `type` should be either 'cli' or 'gui'
+
+    Returns the executable as a byte string.
+    """
+    launcher_fn = '%s.exe' % type
+    if platform.machine().lower() == 'arm':
+        launcher_fn = launcher_fn.replace(".", "-arm.")
+    if is_64bit():
+        launcher_fn = launcher_fn.replace(".", "-64.")
+    else:
+        launcher_fn = launcher_fn.replace(".", "-32.")
+    return resource_string('setuptools', launcher_fn)
+
+
+def load_launcher_manifest(name):
+    manifest = pkg_resources.resource_string(__name__, 'launcher manifest.xml')
+    if PY2:
+        return manifest % vars()
+    else:
+        return manifest.decode('utf-8') % vars()
+
+
+def rmtree(path, ignore_errors=False, onerror=auto_chmod):
+    """Recursively delete a directory tree.
+
+    This code is taken from the Python 2.4 version of 'shutil', because
+    the 2.3 version doesn't really work right.
+    """
+    if ignore_errors:
+        def onerror(*args):
+            pass
+    elif onerror is None:
+        def onerror(*args):
+            raise
+    names = []
+    try:
+        names = os.listdir(path)
+    except os.error:
+        onerror(os.listdir, path, sys.exc_info())
+    for name in names:
+        fullname = os.path.join(path, name)
+        try:
+            mode = os.lstat(fullname).st_mode
+        except os.error:
+            mode = 0
+        if stat.S_ISDIR(mode):
+            rmtree(fullname, ignore_errors, onerror)
+        else:
+            try:
+                os.remove(fullname)
+            except os.error:
+                onerror(os.remove, fullname, sys.exc_info())
+    try:
+        os.rmdir(path)
+    except os.error:
+        onerror(os.rmdir, path, sys.exc_info())
+
+
+def current_umask():
+    tmp = os.umask(0o022)
+    os.umask(tmp)
+    return tmp
+
+
+def bootstrap():
+    # This function is called when setuptools*.egg is run using /bin/sh
+    import setuptools
+
+    argv0 = os.path.dirname(setuptools.__path__[0])
+    sys.argv[0] = argv0
+    sys.argv.append(argv0)
+    main()
+
+
+def main(argv=None, **kw):
+    from setuptools import setup
+    from setuptools.dist import Distribution
+    import distutils.core
+
+    USAGE = """\
+usage: %(script)s [options] requirement_or_url ...
+   or: %(script)s --help
+"""
+
+    def gen_usage(script_name):
+        return USAGE % dict(
+            script=os.path.basename(script_name),
+        )
+
+    def with_ei_usage(f):
+        old_gen_usage = distutils.core.gen_usage
+        try:
+            distutils.core.gen_usage = gen_usage
+            return f()
+        finally:
+            distutils.core.gen_usage = old_gen_usage
+
+    class DistributionWithoutHelpCommands(Distribution):
+        common_usage = ""
+
+        def _show_help(self, *args, **kw):
+            with_ei_usage(lambda: Distribution._show_help(self, *args, **kw))
+
+    if argv is None:
+        argv = sys.argv[1:]
+
+    with_ei_usage(
+        lambda: setup(
+            script_args=['-q', 'easy_install', '-v'] + argv,
+            script_name=sys.argv[0] or 'easy_install',
+            distclass=DistributionWithoutHelpCommands, **kw
+        )
+    )